• Title/Summary/Keyword: Endogenous

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Role of Endogenous Nitric Oxide in the Vasorelaxation Induced by High Calcium Environment in vitro

  • Lee, Jong-Eun;Lee, Byung-Kook;Ahn, Hyun-Taek;Ahn, Byoung-Hee;Kang, Jung-Chaee
    • The Korean Journal of Physiology
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    • v.26 no.2
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    • pp.123-128
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    • 1992
  • The present study was undertaken to examine if endogenous nitric oxide is partly responsible for the high calcium induced vasorelaxation in vitro. Isolated porcine coronary arterial rings were suspended in the tissue chamber and their changes in isometric tension were recorded. KCI little affected the vascular tension in the calcium free media, but subsequent addition of cumulative doses of $CaCl_3$ from 1 to 40 mM caused a contraction followed by complete relaxation. The maximum tension was noted at the calcium concentration in the media of 5 mM, and then the tension progressively declined at 10-40 mM. The relaxation was slightly attenuated in the endothelium-denuded preparation. The relaxation was converted into a contraction by the addition of methylene blue. The relaxation response was not affected in the presence of indomethacin, but was significantly attenuated by $N^w-nitro-L-arginine$ methyl ester pretreatment. These results suggest that the calcium induced vasorelaxation is in part attributable to the release of endogenous nitric oxide.

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FUNCTIONAL EXPRESSION OF A PEPTIDE TRANSPORTER IN XENOPUS OOCYTES

  • Oh, Doo-Man
    • Journal of Pharmaceutical Investigation
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    • v.23 no.3
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    • pp.31-40
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    • 1993
  • It is essential to clone the peptide transporter in order to obtain better understanding of its molecular structure, regulation, and substrate specificity. Characteristics of an endogenous peptide transporter in oocytes were studied along with expression of an exogenous proton/peptide cotransporter from rabbit intestine. And further efforts toward cloning the transporter were performed. The presence of an endogenous peptide transporter was detected in Xenopus laevis oocytes by measuring the uptake of $0.25\;{\mu}M\;(10\;{\mu}Ci/ml)\;[^3H]-glycylsarcosine$ (Gly-Sar) at pH 5.5 with or without inhibitors. Uptake of Gly-Sar in oocytes was significantly inhibited by 25 mM Ala-Ala, Gly-Gly, and Gly-Sar (p<0.05), but not by 2.5 mM of Glu-Glu, Ala-Ala, Gly-Gly, Gly-Sar and 25 mM glycine and sarcosine. This result suggests that a selective transporter is involved in the endogenous uptake of dipeptides. Collagenase treatment of oocytes used to strip oocytes from ovarian follicles did not affect the Gly-Sar uptake. Changing pH from 5.5 to 7.5 did not affect the Gly-Sar uptake significantly, suggesting no dependence of the endogenous transporter on a transmembrane proton gradient. An exogenous $H^+/peptide$ cotransporter was expressed after microinjection of polyadenylated messenger ribonucleic acid $[poly\;(A)^+-mRNA]$ obtained from rabbit small intestine. The Gly-Sar uptake in mRNA-injected oocytes was 9 times higher than that in water-injected oocytes. Thus, frog oocytes can be utilized for expression cloning of the genes encoding intestinal $H^+/peptide$ cotransporters. Using the technique size fractionation of mRNA was sucessfully obtained.

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Effects of Dietary Cellulose on the Basal Endogenous Loss of Phosphorus in Growing Pigs

  • Son, A.R.;Kim, B.G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.3
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    • pp.369-373
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    • 2015
  • An experiment was conducted to determine the effect of cellulose concentration in diets containing no phosphorus (P) on the basal endogenous loss (BEL) of P in growing pigs. Twelve barrows (an initial mean body weight = $49.6{\pm}3.2kg$) were individually housed in metabolism crates. Pigs were allotted to 4 experimental diets according to a cross-over design with 12 animals and 2 periods. Four P-free diets were mainly based on corn starch, sucrose, and gelatin, and were formulated to contain 0%, 4%, 8%, or 12% cellulose. Each period consisted of a 5-d adaptation and a 5-d collection period. The marker-to-marker method was used for fecal collection. The feed intake (p<0.05, linear and quadratic) and dry feces output (p<0.01, linear and quadratic) were increased with increasing dietary cellulose concentration. However, P concentration in the feces was decreased (p<0.01, linear and quadratic) with increasing dietary cellulose concentration. There was no significant difference in total P output and the BEL of P as mg per kg DMI (ranging from 157 to 214 mg/kg of dry matter intake) among experimental diets. However, values for the apparent total tract digestibility of energy, dry matter, organic matter, crude protein, and calcium were linearly decreased (p<0.01) with increasing cellulose concentration in the diet. In conclusion, dietary cellulose affected the amount of feces and digestibility of energy and nutrients, but did not affect the endogenous loss of P.

A Study on the Reasons of Development Gap in Rural Community Development : The Application of Neo-Endogenous Development (농촌마을 발전 격차의 원인에 대한 연구: 신내생적 발전론의 적용)

  • Kim, Tae-Yeon
    • Korean Journal of Organic Agriculture
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    • v.28 no.1
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    • pp.69-93
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    • 2020
  • The paper is to compare two villages in Songak-myeon, Asan, Cnungnam Province in Korea. It tries to show how the joint village project, which began with the support of the same external organization, produces different results depending on the internal conditions and circumstances of the village. From the end of the 1990s, Pyeongchon-ri and Sugok-ri started developing villages under the influence of the environmentally friendly farming movement. And subsequent supports were provided by local organizations for the development of the village. However, the village project in Sugok-ri, which focused on economic performance, later turned out to be a failure, and the residents changed to pursue activities for their own economic interests individually. On the other hand, In Pyeongchon-ri, the cooperation among villagers was strengthened in implementing support projects by similar external agencies. In addition, community ties and identity have been strengthened as problems have been solved through cooperation among residents in the process of promoting the village project. Nevertheless, projects undertaken in Pyeongchon-ri for the purpose of increasing economic performance was all failed. Through these findings, the paper asserts that the neo-endogenous development approach utilizing external support on the basis of internal cooperative network among villagers must be a very useful method for rural development in contemporary societies.

Dormancy-related Change in Endogenous ABA, Batatasin, and Sugar in Stored Tuber and Bulbil of Chinese Yam

  • Lee, In-Jung;Kim, Sang-Kuk;Lee, Sang-Chul;Park, Tae-Shik;Kwon, Soon-Tae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47 no.4
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    • pp.297-300
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    • 2002
  • Endogenous ABA and batatasins were first quantified in the stored tubers and bulbils of the Chinese yam, Dioscorea opposita Thunb. cv. 'Tsukune' by GC-MS with comparison of internal standard, and sugar content was also analyzed by HPLC with comparison of external standard. Endogenous ABA content in stored tubers and bulbils was rapidly decreased as storage period prolonged. ABA content of the bulbils was always higher than that of tuber during storage periods. All batatasins of stored tubers and bulbils at 30 days after storage decreased steadily compared to 120 days after storage. On the contrary, batatasin-Ⅲ of the stored tuber and bulbils was only decreased at 60 days after storage. In Dioscorea opposita Thunb. cv. 'Tsukune' like D. japonica, D. alata, and D. bulbifera, may be controlled by endogenous batatasins and ABA, In these compounds, batatasins rather than ABA might be closely related to dormancy-inducing compound during dormancy of the Chinese yam, Dioscorea opposita Thunb. cv. Tsukune.

A Study on the Theory of Mountain Village Region in Korea of Globalization Age (세계화 시대의 한국 산지촌에 관한 이론연구)

  • Oh, Nam-Hyun
    • Journal of Korean Society of Rural Planning
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    • v.13 no.4
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    • pp.43-51
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    • 2007
  • The propose of this paper is to study a theory on the research of mountain village region in korea of globalization age. The theory of this study is over-depopulation region study, endogenous regional development theory and resident organization, localities and new regional studies The case of over-depopulation region study, which population and land use of mountain village region due to urbanization and industrialization are changed by external factors. However, the case of some region is changed by internal factors of community residents. The endogenous regional development theory and have approached by investment policy of authorities of the mountain village region development and resident organization. The development of mountain village region have to described simultaneously both behavior strategy of community residents and investment policy of the authorities. According to localities and new regional studies, which agricultural products of mountain village region is extended to big-scale city by the progress transportation-communication and globalzation So, the research of mountain village region have to explained together intra with inter region. In the future, the research of mountain village region has to described all of case of over-depopulation region study, endogenous regional development theory, localities and new regional studies.

Effect of Red Ginseng, White Ginseng and Diethyldithoicarbamate in Irradiated Mice (방사선 피폭 마우스에서 홍삼, 백삼 및 diethyldithoicarbamate의 효과)

  • 김성호;이해준;김세라;이종환;조성기;나승렬;손창호;신동호
    • Journal of Ginseng Research
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    • v.25 no.2
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    • pp.68-73
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    • 2001
  • Studies were performed to determine the effect of red ginseng and white ginseng on jejunal crypt survival, endogenous spleen colony formation, and apoptosis of jejunal crypt cells in irradiated mice. The radioprotective effect of ginseng was compared with the effect of diethyldithocarbamate(D). Jejunal crypts were protected from irradiation by pretreatment of red ginseng (50 mg/kg B.W., I.P. at 36 and 12 hours before irradiation) and white ginseng (50 mg/kg B.W., I.P. at 36 and 12 hours before irradiation). Red ginseng administration before irradiation and both pretreatment and posttreatment (50 mg/kg B.W., I.P. at 30 minutes after irradiation) of white ginseng resulted in an increase of the formation of endogenous spleen colony. the frequency of radiation-induced apoptosis in intestinal crypt cells was also reduced by both pretreatment and posttreatment of red ginseng, and pretreatment of white ginseng. The radioprotective effect of DDC (1000 mg/kg B.W., I.P. at 30 minutes before irradiation) on jejunal crypt survival and apoptosis was similar to those of ginseng treatment. Treatment with DDC showed no significant modifying effects on formation of endogenous spleen colony. These results indicated that ginseng might be a useful radioprotector. Further studies are needed to characterize effective radioprotective components and mechanism of ginseng.

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Stimulatory Effect of Ginseng Saponin on Endogenous Production of Nitic Oxide

  • Kim, Hye-Young
    • Proceedings of the Ginseng society Conference
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    • 1998.06a
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    • pp.199-207
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    • 1998
  • Ginseng saponin (G5) purified from Panax ginseng, increase renal blood flow in rats. Nitric oxide (NO) is thought to be a substance endogenously released by G5 in preconstricted lungs and cultured endothelial cells. The present study aims to determine whether G5 could stimulate endogenous 1'elease of NO in rat kidney and urine levels of the stable NO metabolites, nitrite (NO,) and nitrate (NO,) and urinary COMP levels were measured 8 hr after a single intraperitoneal injection of GS (200 mg/kg) Into rats. The effects of the WO synthesis inhibitor, Nu-nitro-L-arginine methyl ester, .1nd the NO precursor, L-arginine, on the G5-induced changes were also determined. The activity of NO synthase, as determined by conversion of ('"C)-L-arginine to ('"C)-L-citrulline, in whole kidney, glomeruli and cortical tubules were also investigated. A single injection of GS resulted in endogenous production of NO as reflected by increase in serum and urine levels of N021N03 and urinary cGMP levels, which were inhibited by the addition o ( N-nitro-L-arginine methyl ester and restored fly L-arginine. GS also stimulated the activity of NO synthase in whole kidney as well as glomeruli and cortical tubules, and Nu-nitro-L-arginine methyl tilter significantly prevented this increase. In conclusion, GS stimulates endogenous NO production and thus, may play a protective role 1 11 the kidney by modulating renal blood flow.

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Circular RNAs in and out of Cells: Therapeutic Usages of Circular RNAs

  • Mingyu Ju;Dayeon Kim;Geurim Son;Jinju Han
    • Molecules and Cells
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    • v.46 no.1
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    • pp.33-40
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    • 2023
  • RNAs are versatile molecules that are primarily involved in gene regulation and can thus be widely used to advance the fields of therapeutics and diagnostics. In particular, circular RNAs which are highly stable, have emerged as strong candidates for use on next-generation therapeutic platforms. Endogenous circular RNAs control gene regulatory networks by interacting with other biomolecules or through translation into polypeptides. Circular RNAs exhibit cell-type specific expression patterns, which can be altered in tissues and body fluids depending on pathophysiological conditions. Circular RNAs that are aberrantly expressed in diseases can function as biomarkers or therapeutic targets. Moreover, exogenous circular RNAs synthesized in vitro can be introduced into cells as therapeutic molecules to modulate gene expression networks in vivo. Depending on the purpose, synthetic circular RNA sequences can either be identical to endogenous circular RNA sequences or artificially designed. In this review, we introduce the life cycle and known functions of intracellular circular RNAs. The current stage of endogenous circular RNAs as biomarkers and therapeutic targets is also described. Finally, approaches and considerations that are important for applying the available knowledge on endogenous circular RNAs to design exogenous circular RNAs for therapeutic purposes are presented.

Endogenous Development Strategy of Technopolis in Korea: Case of Daedeok INNOPOLIS

  • Lee, Eung-Hyun;Oh, Deog-Seong
    • World Technopolis Review
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    • v.5 no.1
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    • pp.2-18
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    • 2016
  • The development of Technopolis and the establishment of innovative ecosystem have made an important contribution in South Korea's latest industrial development and economic growth. Particularly, Daedeok INNOPOLIS which is responsible for the central role in the national science technology advancement was founded as the Science Town in the 1970s. Since then, it has undergone three-phases of development: Science Park, Technopolis and Innovation cluster. As the result of the transition, Daedeok INNOPOLIS currently serve as the leading role for achieving sustainable economic growth, employment promotion, national and regional innovation. In order to accelerate the progress for success, Daedeok INNOPOLIS have arranged an opportunity for 21st century new industry development, improved growth of technology-intensive SMEs, reinforced academic-industrial cooperation, and established innovative ecosystem. Daedeok INNOPOLIS is considered as an outstanding case of endogenous development strategy of Technopolis. This study attempts to consider the endogenous development strategy of Technopolis in Korea through the analysis of development characteristics of Daedeok INNOPOLIS in two different perspectives: changes of spatial structure and establishment of innovation ecosystem. Daedeok INNOPOLIS have experienced a series of endogenous growth that is consisted of advancement strategy and structural changes, which allowed Daedeok research town to grow into an innovative cluster. A sign of growth of Daedeok INNOPOLIS became apparent when its strategy to reinforce the academic-industry cooperation system by promoting participation from universities helped to overcome a functional limitation as a research institute integrated for the establishment of innovative ecosystem. Since then, the center for creative economy and innovation established in cooperation with large enterprise, has a role to build a startup ecosystem and to promote next level of development such as proactive fostering of venture companies for sustainable technopolis development.